This invention relates to a windshield wiper blade used mainly on the outer surfaces of the front and/or rear windows of the driver/operator compartments of such vehicles as automobiles and railroad locomotives.
In the past, in addition to blades having a one-blade construction, blades of two- and three-blade constructions have been proposed for use to wipe rainwater, etc., from the surfaces of the windows of vehicles. However, wiper blades of a one-blade construction have not provided sufficient wiping of the rainwater, etc., thus allowing some water to remain on the glass, and also this type of wiper blade has lacked durability, thus failing to provide a long useful life.
For wiper blades with a two-blade construction, although the useful life has been longer than that of the one-bladed wiper blades, because the edges of both blades came together in close contact during the back-and-forth movement of the wiper, this type of wiper blade, just as with the one-bladed wiper blade, did not provide sufficient wiping of the rainwater, etc., (especially when an oily film is present), thus allowing some water to remain on the glass and failing to ensure the necessary safety.
In addition, for wiper blades having a three-blade construction, because the edges of the two outer blades came in close contact with the edge of the center blade during the back-and-forth movement of the wiper, the wiping performance has been substantially no more effective than that of the two-bladed wiper blade, thus making the costs considerably high in relation to the wiping performance.
Furthermore, because conventional wiper blades generally use their edge to wipe away the rainwater, etc. during the back-and-forth swinging motion of the blade, the edge of the blade must be formed with a corner angle of exactly 90.degree.. Because of this, during the production of the wiper blades, for example, when a pair of long wiper blades are injection molded with their edges abutting, the abutting edges had to be cut in the longitudinal direction accurately so that the corner angles would be exactly 90.degree., and this cutting process required a considerable amount of precision, thus making the production work rather difficult.
It is a general object of the present invention to provide a wiper blade which does not require that the edge of the blade be specially cut accurately at a right angle, thus simplifying the production process, and also which, in comparison to conventional wiper blades, provides both superior wiping performance, allowing less rainwater, etc., to remain on the glass surface, and having a longer useful life.